Party-line revertible ringing system



Nov. 29, 1927. 1,651,017 I 4 e. DEAKIN PARTY LINE REVEHTIBLE RING-ING SYSTEM Filed Feb. 25. 1926 4 Sheets-Sheet l Wye/Var Gem/d flea/rm.

Nov. 29, 1927.

e. DEAKIN PARTY LINE REVER'I'IBLE RINGING SYSTEM Filed Feb. 25. 1926 4 Shets-Sheet 2 Af/jc G. DEAKIN PARTY LINE REVERTIBLE RINQING SYSTEM Fileg Feb. 25. 1926- 4 Sheets-Sheet 4 by MA Patented Nov. 29, 1927.

UNITED STATES PATENT oFFica GERALD DEAKIKOF Amwaaamm Assreiion TO BELL TE LE PrioNiE LABORA- TORIES, INCORPORATED, or NEW YORK, N. Y., a CORPORATION OF NEW YORK.

PARTY-Linn REVER-TIBLE Rmeino sesame.

Application. file l February 25, 1926, Serial rib. 90,459, in Great Britain February 26, 192 5.

calls over a two party line. v

A feature or the invcntionlies in the provision and means for signaling the other party on a two party line without dialing.

A. further feature of the invention lies in the provision of a key for causing the application of ringing current to the party line.

These features will become more clearly apparent from a consideration of the following description; drawings and appended claims. I

In the drawings, Fig. 1 shows a two party subscribers linecircuit, together with a primary line finder.

Fig. 2 shows a secondary line finder and selector switch for extending calls. It also shows a sender selector in the space below the broken line.

Figs. 3 and. 4 show a register sender for recording the digits corresponding .to the wanted line and torcon'trolling selections.

Fi 5 shows the manner in which the Figsi l to 4 should be arranged to disclose this invention.

The present invention is particularly applicable to a system such as that disclosed in U. S. Patent 1,479,554 granted January 1, 1924 to L. ,Polinkowsky et al; and has been disclosed in such a manner that Figs. 1 to 4 of the present invention can be substituted for Figs. 1. to 4 of the Polinkowsky patent.

In accordance with the general features of this invention, a party line subscriber such as the subscriber at substation B, wishing to call the second party on his line, will remove the receiver from the hook and, upon receiving the dial tone which informs him that the apparatusv is ready to recei've dialing. will depress his non-locking key 150 and hold it depressed until his bell rings. He may thereupon release key 150. The bells of both stations are rung simultaneously for a predetermined period of time after which the ringing ceases.

Should the wanted station fail to answer in response to this ringing the calling subscriber must hang up and recall in the above manner. r e a When the cal ed ubscmber nswers the pairs and when current for conversationis supplied from the connecting circuit shown in Fig. 2, the sender being disconnected automatically.

A comparison of the drawings of the present application with those of the above identified patent to Polinkojwsky et al..wi1l

show that the only additional equipment at the subscribers substation is the key iaoand condenser 151 in each substation circuit. At the central office the additionalequipment consists of a difi'erentialrelay 153, a second relay 154 and interrupters 155, 156 and 157 and resistance 158. V v V T he detailed operation of the circuits may be described as follows: lVhen the subscriber at one ofthe substations. say B, initiates a call, it causes the energization ofline relay 201 which in turn causes the energization of the oo mmon'start relays 204 and connects -battery through theserelaysto terminal 210marking the line in the banks of the primary line finders. The operation of the start relays 204 closes a circuit for energizing the power magnets 211 of the free first line finders in the group serving the calling line. Thebriish carriages oi the free. first line findersrotate. lVhen on of these reaches terminal 210 it completes a circuitfrom battery through the windings of the'start relays 204, terminal 210. the right high resistance winding of testingrelay 214 to ground. The operation of relay ,214 connectsgroundthrough the left low resistance winding and :through the winding of relay 212 in parallel to terminal 210 making the terminal non-selectable to other first line finders. The operation of relay 212 opens the circuit of the power magnet .and closes the circuit of the holding magnet 215 and o fthe start relays 216 of the secondary line finders, It'alsooonnects battery over, the back contact of relay 213, front contact of relay212 to terminal 230 to identify this primary line finder as calling.

The secondary linefinders are divided into free the corresponding sequence switches 220 are held either in pos tion 18 or position 1. Only the line finder ofa connecting circu t of which the sequence, switch 220 is lIlPOSP tion 1 is able'to sear h for a calling first line finder. ,The operation of start relays 216 causesthe energization of relay 222' in such connecting circuit over the upper contact of cam 260; Relay 222 operates in this cirtheconnecting circuits are cuit and closes a circuit for energizing the the power magnet 221 in a circuit over the lower contact of cam 261, back contact of relay 232, front contact of relay 222, back contact of relay 231 to ground. The brush carriage of the secondary line finder rotates under the control of power magnet. 221. On reaching terminal 230, test relay 234-. is energized in a circuit from battery on terminal 230, lower contact of cam 268, right high resistance winding of relay .3 1, right back contact of relay 22 1, lower contact of cam 227, lower contact of cam 281 to ground. Relay 234 attracts its armature and connects its left hand low with the windingot relay to ground, marking terminal 230 busy. .Relay 232 when energized causes the cnergization of sequence switch 220 in a circuit extending over the upper contact of cam front contact of relay 232, front, contact of relay 222, back contact of relay 231 to ground. Sequence switch 220 moves out of position 1 and into position 4-.

When sequence switch 220 passes position 2 thehigh resistance winding of relay 234 is disconnected at the bottom contact of cam 227,, and relay 23.41 is maintained energized over its low resistance winding and the winding of relay 232. In position 3 ct switch 220 a circuit is establish-ed'from ground over cam 259, back contact of relay 224C, winding of relay 235, terminal 238, winding of relay 213, windingoi cut-oft" relay 207 to battery. The energization of cut-off relay 207 deenergizes relay 201 and brings the brush carriages o'l any primary or secondary line finders which are still hunting to. rest. Belay 231 and retar ation coil 23'Z are connected to the calling line at this time. The advance of sequence switch 220 to position 4: opens the holding circuit of relay 234-. v i

In position 1 of sequence switch 220, the sequen1e switch 280 ot the connector circuit is energized to hunt for an idle register sender. The register sender of Figs. 3 and 1 is connected to the connecting circuit when sequence'switciti 280 is. in position 1 or position 7. Assuming this register sender to be idle, as soon as sequence switch 280 reaches position or position 6 a circuit is ("lOSCd from battery through the right winding of relay 323, upper contact of "am 322, conductor 293, lower contact of "am 26%,lowcr contact of cani2et6, right winding of relay 23 1, upper contact of cam 281 to ground. The cuttings of cum 261- are made wide enough to complete this circuit at the time that the upper cuttings in the half positions or cam 281 are closed, so that relay 23 1- operates and closes its'holding circuit over its front contactand' the winding of relay 232 to ground. The operation of relay opens the circuit of sequence switch 280 to resistance winding in series bring that sequence switch to rest when it reaches-position 1. or 7.

Sequence switch 220 is thereupon advanced to position in a circuit through the winding of sequence switch 220, upper con- 235, lower contacts of cams 271 and 272,

the back contacts of relay s, windings of ditl'erential relay 153, secondary windings of dial tone coil 324i and the windings of steppii'ig relay 325 ot'thc register sender. Relay operates in this circuit but relay 153 being differential does not.

The operation of relay 323 in the previously traced circuit closes a circuit from ground over its front contact and left winding, through the winding of sequence switch magnet 320 tov battery advancing that sequence switch to position 3. With sequence switch 320 in positions 2 and 3 the primary circuit of dial tone coil 32 1 is closed over the lower contact of cam 332 and interrupter 333. A. tone is thereupon induced in the dialing circuit of the subscriber and a tone is produced in the receiver at substation? In the case of a call to a subscriber on some other line, the subscriber at substation B would now operate his dial and under the control of sequence switch 320 would set the registers 100, etc. of Fig. 4'. Since this is a call to another party onthe same line the subscriber now depressesv th key 15 The operation of key opens the loop circuit at a substation and connects ground to conductor 159 through the substation ringer 160. This holdsrelay 325 operated and un balances the circuit through relay 153 and that relay also operates. Relay 15 1 and interrupters 155, 156 and 15'? control the re vertive calling. V

Interrupter closes a circuit to ground for about one tenth are second once every four seconcs or any other interval 'whiih may be desfinble for a ringing period. This circuit is extended over the front contact oi relay 153, through the winding of relay 154;. Interrrmter 156 is arranged to close its conducting segment at the same time that int rrupter chases but it does not open its contact until a tenth of a second before interrupter 155 again closes its contact. Intcrrupter is'also arranged to close its conducting segment at the same time as interrupters and 156 but itopens its ronductiiui; segment two-tenths of a second bei'ore interrupter 155 recloses .its contact.

Therefore the operation of relay 154:, due to the closure ofinterrupter 155, completes a locking circuit for itself through interrupter 156. The operation of relay 15% also connects ringing current over its outer left iii! Ill

front contacts to the two sides of the calling line thus ringing the bells of suhsta tions A and B- siinultaneously. A holding circuit forrelays 325 and 153 is also co1npleted through the left windings of these relays and the inner left front i'ontac-t of relay 15stto ground through interrupter 157 thus preventing thepreniature release of. the register sender. As soon as ringing starts, key 150 may be releasec since the ringing is now under the control of relay 15%. As the potential applied to the two sides of theline is the same, no appreciable current will pass through the transmitter even though it is connected to the line.

As the interrupters approach the end of: their cycle, interrupter 157 will open tact and release relays 153 and A tenth of a second later interrupter 156 will open and release relay 15a. Since relay 153 is alreadyreleased the closure ot the contact of interrupter 155 is ineilective at this time.

In the meantime the advance oi? sequen e switch 320 from position'2 ope-nsthe circuit of relay 323' and that: relay releases. lVhen relay 325 released as above d scribed a car cuit was closed from battery through the winding of relay 334, left contact oi? cam 34:2 to ground atthe back contact relay 325. Relay 334 in operating closes a circuit from battery through the right winding of relay 323, front contact of relay 334 to ground. Relay 323 closes a circuit for advancing sequence switch 320 out of position 3. In passing'through positiona with relay released, a circuit is closed from-battery through the winding of relay 339, upper contact of cam 3&8, to ground at the bacli contact oi? relay 325. Relay 339 locks over its left front contact and the upper contact of cam 340.

relay 22, lower contact of cam 247, lower contact ot cam 2S6, conductor 296,-upper contact of cam 376, right front contact of relay 339 to ground. Relay 222 operates in this circuit and closes a circuit from battery through the winding of magnet- 220, lower contact or cam 263, back contact of relay 232, front contact oi rela 222, back cont'aat of relay 231 to ground. Sequence switch 220 is advanced to position 6 in this circuit.

The operation of relay 339 prevents the reeperation of relay 325 at this time and relays an and 323 are reoperated in position 5 of sequence s 'itcll 320 to advance that sequence switch to position 8. This operation is repeated in positions 3; 10 and 12 advancing sequence switch 320 to position let. It is advanced out of position 14 by means of a circuit over the lower contact of cam 348 and back contact of relay 325.

lVith sequence switch 350 still in position 1 relay 323 is operated in position 15 of switch 320 over the lower contact of cam 322 its con-' A circuit is thenclosed "from battery through the winding of and lower contact of cam 369, advancing sequence switch 320 toposition 17. telay is 'reoper'ated in position 1' over the right contact of cam 342, backv contact oi relay 326, lower contact of cam 3&0 in turn rc'operating' relay 323 and advancing sequence switch 320'to position 1. When sequence switch 320 leaves position 15 the locking circuit of relay 339 is opened and that relaj releases opening the circuit of relay 2221 Sequence switch 220'is then advanced to position 8 in a circuit over the lower contact of cam 265,- hack contact ot' relay 222, back contact of relay 231 to ground.

Since the selector switch has not been operated a local circuit is closed in position 3 of sequence switch 220 from battery over the upper contact of cam 261', over normal contact 269 of the selector through the winding of relay'232. Relay 232 operates and closes acircuit from battery through the winding of sequence switch magnet 220, upper contact of cam 263, front contact of relay 232, upper contact of cam 227, lower contact of cam 281 to ground, advancing sequence switch 220 to position 9. In position 9 the previously traced circuit over the back con tacts of relays 222 and 231 is again closed sequence switch 220 advanced to position 10.

WVith sequence switch 220 in position 10 the calling subscribers line is connected through relay 231 to battery and through retardation coil 237'to groundi The subscri er receives talking current through relay 231 and the operation oftliat relay prevents the release of the connecting circuit until both subscribers have hung up. Since no outgoing connection has been established over the connector switch, relay 262 is not operated and a circuit is closed from battery through the winding of sequence switch magnet 22) contact of cam 267 to ground at the back contact of relay 262 advancing sequence switch 220 to position 13. I

Sequence switch 220' remains in this position until relay 231 is released by the disconnection of the two subscribers. The further release of the apparatus isas described in the above identified patent to L.' Polinkowsky et al.

WVhat is claimed is:

1. In a telephone exchange system, a telephone exchange, a subscribers line extending to said exchange. apair of substations on said line, an auxiliary calling device at each substation and means at said exchange responsive to the operation of said auxiliary calling device at one station to signal both substations on said line.

2. In a telephone exchange system. a telephone exchange, a s'ubscribers line extending to said exchange, a pair of substations on said line, an auxiliary calling device at each substation, signaling means at said exchange, and means at the exchange responsive to lit) the operation of said auxiliary calling device to close a signaling circuit for both substations on said line for a predetermined time only.

3. In a telephone system, a telephone ex change, subscribers lines connected with said exchange, a pair of substations being connected to certain of said lines, means at said exchange for establishing connections between subscribers lines, control apparatus for directing the establishment of such connections, an, auxiliary calling device at the substations of lines to which a pair oi substations are connected, means in said control device respons ve to the operation of said auxiliary ailing device to signal the substations on said line and means for disconnecting said control device.

l. In a telephone exchange system, subscribers lines, including party lines, automatic switches for extending connections from said lines, a common sending device including a plurality of registering devices for controlling the operation of said switches, substation means to variably position said registering devices, means in said sending device for applying ringing current to calling party lines, and substation means for rendering said latter means effective independently of said registering devices.

5. In a telephone exchange system, subscribers lines, including party lines, automatic switches for extending connections from said lines, a common sending device including a plurality of registering devices for controlling the operation of said switches, substation means to variably position said registering devices, means in said sending device ior applying ringing current to calling party lines, and means operable independent to said register positioning means to render said ringing current applying means effective.

6. In a telephone exchange system, subscribers lines, including party lines, automatic switches for extending connections from said lines, a common sending device including a plurality of registering devices for controlling the operation of said switches. substation means to variably position said registering devices, means in said,

sending device for applying ringingcurrent to calling party lines, means operable inclependent of said registering devices to render said ringing current applying means eilective, and means for thereupon disconnecting said sending device.

7. In a telephone exchange system, subscribers lines, including party lines, automatic switches for extending connections from said lines, a common sending device including a plurality of registering devices for controlling the operation of said switches,

current to calling lines,

substation means to variably position said registering devlces, means in said sending device for applying ringing current to calling party lines, means operable independent 8. In a telephone exchange system, subscribers lines, including party lines, a link circuit, means for extending a calling line to said link circuit, automatic switches tor further extending connections from said lines, a common sending device including a plurality of registering devices for controlling the operation of said switches, substation means to variably position said registering devices, means in said sending device for applying ringing current to calling party lines, means operable independent of said registering devices for rendering said ringing current applying means effective, means for thereupon disconnecting said sending device, and means for supplying talking current from said link circuit to said calling line.

9. In a telephone exchange system, subscribers lines, including party lines, automatic switches for extending connections from said lines, a common sending device including registering devices for controlling the operation of said switches, a pulsing circuit for associating said registering devices with a calling line,substation means for controlling said pulsing circuit to variably position said registering devices, means in said sending device for applying ringing in said pulsing circuit and substation means for operating said relay to render said current applying means effective.

10. In a telephone exchange system, subscribers lines, including party limis,'automatic switches for extending connections from said lines, a common sending device including registering devices for controlling the operation of said switches, a pulsing circuit for associating said registering devices with a calling line, a pulsing relay and a,

differential relay in said circuit, substation means for controlling said pulsing relay to variably posltion said registering devices,

means in said sending device for applying ringing current to calling lines, and substation means for operating said differential relay to render said current applying means effective without positioning said registering cevices to control said switches. i

In witness whereof, I hereunto subscribe my name this 2 day of February, A. D., 1926.

GERALD DEAKIN.

differential relay 

